Wire with magnetic insulation



Jan. 11, 1966 M. BAERIMANN 3,229,030

WIRE WITH MAGNETIC INSULATION Filed Oct. 26, 1961 2 Sheets-Sheet l IN V EN TOR.

MAX BAERMANN 36 FIG. 4a ww ATTORNEY Jan. 11, 1966 M. BAERMANN WIRE WITH MAGNETIC INSULATION 2 Sheets-Sheet 2 Filed Oct. 26, 1961 I FIG.9

FIG. ll

INVEN TOR. MAX BAER MANN ATTORNEY United States Patent 3,229,030 WIRE WITH MAGNETIC INSULATION Max Baermann, Bensberg, Wulfshof, Bezirk Cologne (Rhine), Germany Filed Oct. 26, 1961, Ser. No. 147,967 Claims priority, application Germany, Feb. 9, 1957, B 43,454 8 Claims. (Cl. 174-117) This application is a continuation-in-part of my copending application Serial No. 66,832, filed November 2, 1960, now abandoned, which was a continuationin-part of my application Serial No. 693,603, filed Oct. 31, 1957, now United States Letters Patent No. 2,959,832.

This invention relates to the art of electrical conductors and more particularily, to electrical conductors that may be mounted directly onto magnetically attractable walls, partitions or other structures without requiring ancillary fastening devices.

In Patent No. 2,959,832, there is described and claimed a flexible permanent magnet comprised of a mixture of a flexible or resilient nonmagnetic binder material and particles of permanent magnetic material dispersed throughout. In some respects, it may be said that the particles of magnetic material are held in close spaced relationship by a flexible binder material. The perma nent magnet particles are magnetized as a group to form a plurality of close spaced, opposite polarity, permanent magnetic poles on one surface of the magnet. These poles can produce a substantial magnetic holding force against a magnetically attractable member.

In accordance with the present invention, an electrical conductor is provided comprised of one or more electrical wires in combination with means formed of a mixture of an elastic or resilient electrical insulating material and particles of permanent magnet material, the magnetic material being magnetized so that at least one surface of the means has a plurality of pairs of magnetic poles. By such an arrangement, the conductor may be attracted to, and held onto, magnetically attractable members such as those found in automobiles, ships, bridges and certain buildings or other magnetically attractable members such as other similar conductors. The shape of the magnetized surface of the mounting means should preferably conform to the shape of the magnetically attractable member, e.g., if the member is flat, then the mounting means for the conductor should have a flat outer surface provided with many pairs of magnetic poles thereon.

The term conductor is used in this specification to define the combination of an electrically conductive member, such as a wire, and the permanent magnetic insulating mounting body affixed to the wire.

Preferably, the mixture of binder and permanently magnetizable particles is applied directly onto the surface of the electric wire by extruding in the conventional way such that it will act as an insulating coating as well as a means for holding the conductor onto a ferromagnetic member or the like. Alternatively, the mixture may be applied over or on one side of conventional wire insulation. In either case, the need for conventional fastening devices and the labor required in wiring with the use of such fastening devices is eliminated. For example, in wiring a ship with the conductor of this invention, it will be necessary only to string the conductor adjacent a steel partition or the like where it will be magnetically attracted to, and held on, the partition. In some cases a cement may be employed to support the conductor onto the mounting structure and the magnetic attraction between the conductor and the structure serves to hold the conductor in position until the cement has hardened. In another case, many separate conductors may be held in a unitary cable or harness by the magnetic attraction without the use of binding straps around the group of conductors. This is accomplished by magnetic attraction between the permanent magnetic mounting bodies of the separate conductors.

Further in accordance with this invention, a conductor unit having a number of electrical wires is provided with a mounting body comprised of a mixture of binder material and permanently magnetizable particles dispersed therein. The mounting body has grooves or similar depressions parallel and between the separate wires to allow a portion of the mounting body and certain wires to be selectively separated when it is desirable to use a smaller number of wires than is provided in the complete conductor unit.

In accordance with another aspect of this invention, a conductor comprised of one or more electrical Wires supported within a permanent magnet mounting body and a strip of ferromagnetic material, such as a mixture of a flexible binder and iron particles dispersed therein are joined by a pressure sensitive adhesive. The ferromagnetic strip is adapted to be separated from the conductor and adhered to a nonferromagnetic structure. Thus, this ferromagnetic strip is used to secure the conductor onto the nonferromagnetic structure.

The principal object of this invention is the provision of a new and improved article of manufacture comprised of an electrical conductor which may be affixed to ferromagnetic members without the need for auxiliary fastening devices.

Another object of this invention is the provision of an electrical conducting member coated with an insulating layer of material which material is permanently magnetic.

Still another object of this invention is the provision of an electrical conductor which may be installed in ships, vehicles and the like with a minimum amount of labor.

Another object is the provision of an electrical conductor which is attracted to other conductors or to magnetically permeable surfaces.

Another object of this invention is the provision of a conductor which will support itself on a magnetically attractable member until a cement sets and secures the conductor to the member.

A further object of this invention is the provision of an electrical conductor having an insulating material provided with a flat surface wherein said flat surface has a number of separate magnetic poles which will secure the conductor onto a flat surface of a magnetically permeable material.

A still further object of this invention is the provision of a conductor unit having a number of parallel wires supported by a mounting body of flexible magnetic material having a flat surface provided with a number of pairs of magnetic pole wherein said unit has grooves or recesses extending between and parallel to said wires so said wires may be separated from said unit and afiixed .to a magnetically permeable member.

The invention may take physical form in certain parts and arrangement of parts, preferred embodiments of which will be described in detail in this specification and illustrated in the accompanying drawings which are a part hereof and wherein:

FIG. 1 is a perspective view illustrating one embodiment of the invention and showing a plurality of electric wires secured to a permanent magnetic mounting body having one substantially flat mounting surface;

FIG. 2 is a perspective view illustrating another embodiment of the invention and showing a plurality of wires secured within a permanent magnetic mounting body having two substantially flat surfaces;

FIG. 3 is a perspective view illustrating still another embodiment of this invention and showing a plurality of wires embedded in a permanent magnetic mounting body so that a portion of the mounting body and one or more 7 tion of the conductor disclosedin FIG. 7;

FIG. 9 is a perspective view'illustrating bodiment of this invention;

' FIG. 10 is a cross-sectional view illustrating a still further embodiment of this invention; and

FIG. 11 is a cross-sectional view illustrating the use of the conductor as disclosed in FIG. 10.

Referring now to the drawings which are for the purpose of illustrating embodiments of the invention and not for the purpose of limiting same, FIG. 1 shows a a further emconductor A having a mounting body 10 comprised of an elastic or flexible plastic material having a fine dispersion of permanent magnetic particles therein and having a generally flat mounting surface 12. By proper magnetization of the articles within the body 12, a variety of patterns of pairs of magnetic poles are provided on the generally flat surface 12. As disclosed in FIG. 1, the particles are magnetized so as to provide transversely extending alternate north and south magnetic poles along the length of the mounting surface 12. Opposite the mounting surface, the mounting body 10 is provided with a plurality of parallel depending ribs 14 each of which receives an electrical wire 16 and securely binds the Wire to the mounting body 10. Since the material forming the mounting body is an electrical insulator, it is not necessary to provide separate insulating means for the wires. However, as shown in FIG. 1, it is possible to provide the wires 16 with an insulating coating 18 before the wires are embedded within the mounting body 10.

Referring more specifically to the material-used in the mounting body 10, the flexible or resilient plastic material may be any of the well-known nonmagnetic or unity permeability materials which will be flexible and resilient at room temperature as Well as having good electrical insulating characteristics. For example, it may comprise polyvinyl chloride which is able to maintain its flexibility and strength While having mixed therewith large amounts of dry, powderedmaterial. The permanent magnetic particles are of permanent magnetic material having the highest possible coercive force and the lowest possible permeability. High coercivity materials suitable for this purpose include the following: Barium ferrite (ironbarium oxide) (BaO.6Fe O bismuth manganese (MnBi); lead ferrite (PbO.6Fe O cobalt ferrite I (CoO.Fe O cobalt platinum (CoPt); a material composed of to 40% barium oxide, 1% to manganese oxide and the remainder iron oxide (as described in German Patent No. 927,259); a material composed of 5% to 40% barium oxide, 4% to 8% chromium oxide and the balance iron oxide (as described also in said German patent); and a material composed of 65 to 88 molecular percent iron oxide, 35 to molecular percent lead oxide and 0.8-8 molecular percent silicium oxide, in which-up to half of the lead oxide content may be replaced by barium oxide or strontium oxide (as described in German Patent No. 1,010,440). The aforementioned permanent magnet materials have all the characteristics of extremely high coercivity and low permeability which are extremely desirable for the present invention. Thus, the coercivity of the material in 100% concentrations should be in excess of 1500 oersteds and preferably 2000 oersteds while the permeability should be less than 2 and preferably unity. These materials also have a good electrical insulating quality and therefore they do not appreciably increase the electrical conductivity of the plastic material.

The permanent magnet materials are preferably ground to a grain size less than 0.30 millimeter and are mixed with the flexible binder in a ratio of 40% to 60% by volume. Actually and desirably, the maximum amount of permanent magnetic material which a given flexible binder is able to have dispersed therein while still retaining its flexible characteristics is desirable. The polyvinyl chloride binder may be either made soft or mixed with softeners and then mixed in a powdered state with the permanent magnetic powder.

In accordance with the preferred embodiment of the present invention, the plastic binder having permanent magnetic particles therein is extruded in a heated state directly onto the wire as is conventional with normal plastic insulated Wires. I

In certain cases it may be possible to apply the body 10 onto wire 16 by dipping the wire in a bath containing the permanent magnetic plastic material in an unhardened liquid form. In either case, the end product will be the same, namely, the wires 16 having a body 10 thereon comprised of the plastic material embedded with permanently magnetic particles.

Referring now to FIG. 2, showing a conductor B having a flexible permanent magnetic mounting body 20 provided with generally flat surfaces 22 and 24. Various arrangements of magnetic poles may be provided on surface22 or on both surfaces 22 and 24. The magnetic poles are arranged in pairs and extend in any desired direction. As is shown, the separate north and south poles extend transversely across the surface 22. A plurality of parallel Wires 26 extend between surfaces 22 and 24 and are embedded Within the mounting body 20 so the mounting body provides the insulation between the separate Wires. Of course, as disclosed in FIG. 1, it is realized that the wires as may be provided with insulation coating before the permanent magnetic mounting body 20 is applied. The use of separate insulating coatings may increase the current carrying capacity of the Wires; however, such insulation does not affect the use of the wires with the permanent magnetic mounting body. The substantially flat surface 22 is attracted to a ferro-magnetic member to secure the conductor B onto the member without requiring any auxiliary fastening devices. Another feature of the structure shown in both FIGS. 1 and 2, is the ability of the mounting bodies 10 and 20 to flex so the conductors may conform with various contours on the mounting member.

Referring now to FIG. 3, a further embodiment of the invention is disclosed. In this embodiment, a conductor unit C has a flexible permanent magnetic mounting body 30 with a generally flat mounting surface 32 provided with appropriate pairs of magnetic poles. As disclosed, the poles extend longitudinally of the mounting body 30 and generally parallel with a number of wires 34. It is realized that other magnetization patterns of the magnetic poles could be satisfactorily utilized.

Of particular importance in this embodiment is the structural form of the permanent magnetic mounting body 30. The substantially flat mounting surface 32 is positioned on one side of the parallel extending wires 34 and a plurality of ribs 36 are provided on the opposite side of the wires. The ribs are so positioned with respect to the Wires that the depression between separate ribs is substantially equidistant between adjacent wires. Lying directly above the depression between the ribs 36 and on the surface 32 are a plurality of longitudinally extending grooves or similar depressions 37 Which divide the surface 32 into separate substantially flat surfaces 33. By this structural embodiment of the flexible permanent magnet mounting body 30, one or moreof the wires and the mounting body portion contiguous therewith, may be separated from the complete unit C. Thus, if one or more wires are to be used, they are separated from the unit without departing from the basic feature of having a flat mounting surface that is attractable to a magnetically permeable material.

FIG. 4 discloses conductor D that has been separated from the unit disclosed in FIG. 3 and includes one wire 34. It is noted that the conductor has a rib 36 and a generally flat surface 33 on the surrounding mounting body 30. This conductor may be mounted onto a ferromagnetic member by placing the flat surface 33 against the surface of the member. The conductor disclosed in FIG. 4a differs from the conductor of FIG. 4 only by the arrangement of the magnetic poles on surface 33.

Referring to FIGS. 5 and 6, the conductor D separated from the unit disclosed in FIG. 3 may be mounted on a ferromagnetic wall or partition 40 which wall or partition has a portion 42 and an angular portion 44. It is noted that the surface or surfaces 33 lie against the curved portion 42 to adequately secure the conductor D on the wall or partition 40. At angular portion 44, the conductor does not extend completely into the angle; however, the slight amount of separation of the conductor from the wall or partition 40 does not seriously deter the support of the conductor by the magnetic attraction with the wall or partition 40. FIG. 6a discloses a conductor E having three wires 34 that are separated from the unit C disclosed in FIG. 3 and the wires are supported on the wall or partition 40 by their separate substantially flat surfaces 33.

In FIGS. 7 and 8 a conductor F is disclosed having an electrical wire 52 coated with a flexible permanent magnetic material in the form of a cylindrical mounting body 54). The particles embedded in the mounting body are magnetized to present a plurality of north and south magnetic poles extending longitudinally along mounting body 50. The use of a conductor with a cylindrical mounting body may be quite limited because when mounting the conductor onto a flat surface, there is only point contact between the mounting body and the flat surface. This point contact does not provide a substantial attraction between the permanent magnetic mounting body and the structure on which it is to be mounted. However, such a conductor may be used satisfactorily when the mounting member has an angular portion extending along the path of the conductor. Thus, a wall or partition 54 having such an angular configuration may utilize the conductor disclosed in FIG. 7.

It is often desirable to provide a number of parallel electrical wires in a small space. This is especially true in electrical control panels and telephone relay stations wherein the wires have heretofore been wrapped or bound into harnesses. The present invention eliminates the bulkiness and complexity of such installations. Thus, referring to FIG. 9, wherein another embodiment of the in vention is disclosed, a number of conductors, G, H and I, each having mounting bodies 60 are stacked one on the other and attracted to each other and to a ferromagnetic wall or partition 68. To make this structure possible, each conductor has generally parallel flat surfaces 62 and 64. The flat surfaces are provided with appropriate north and south poles obtained by magnetizing the particles embedded within the mounting bodies 60. The conductors 66 extend parallel through the separate flexible mounting bodies 60 so that as the various conductors are stacked a desired number or wires are provided. In the past, identification of the wires within a harness was diificult and color coding has been the accepted practice. However, by the use of this embodiment of the invention, the location of the wires through the length of the structure does not change with respect to the various conductors. Thus, color coding of the wires is unnecessary. However, if such coding is desired, it is possible to provide a colored insulation on the wires prior to extruding the flexible plastic magnetic material around the wires.

In some installations, it is necessary to assemble the conductors on a nonmagnetic wall or partition. The embodiment of the invention shown in FIGS. 10 and 11 adapt the embodiment disclosed in FIG. 9 to use on a nonmagnetic wall, such as wooden wall 79. The conductor J has a flexible permanent magnet mounting body provided with substantially flat surfaces 72, 74 either of which surfaces may be magnetized to present a plurality of pairs of north and south magnetic poles. A pressure sensitive adhesive layer 76 secures a magnetic strip 78 onto surface 74. The magnetic strip 78 is flexible and may be comprised of various flexible magnetic structures such as a plastic material with iron particles dispersed therethrough. A plurality of wires are embedded within the mounting body 70 and may be secured onto the wooden wall 79 by first removing the magnetic strip 78 from the mounting body 70 and adhering the strip to a surface of wall 79. Thus, the magnetic strip 78 is exposed and the north and south poles on either surface 72 or surface 74 coact with the magnetic strip 78 to magnetically join the conductor to the magnetic strip 78. In this manner, the conductors are secured to the nonmagnetic wall 79.

Various modifications and applications of the concepts to which this invention is directed may be made without departing from the scope and spirit of the invention as defined by the appended claims.

Having thus described my invention, I claim:

1. In the combination of an elongated electrical conductor and an insulating covering theron, the improvement comprising: said covering being formed from a hardened, flexible electrically insulating material and finely divided permanently magnetizable particles dispersed throughout and embedded within said material, said particles being formed from a permanent magnet material having a low permeability and a high coercivity, and said particles in said insulating covering magnetized along the complete length of said conductor to provide a holding magnet for attracting said conductor onto a ferromagnetic base.

2. The improvement as defined in claim 1 wherein said permanent magnet material is selected from the group consisting of barium ferrite, bismuth manganese, lead ferrite, cobalt ferrite, cobalt platinum, and a material composed of 65 to 80 molecular percent iron oxide, 35 to 15 molecular percent lead oxide and 0.8 to 8 molecular percent silicon oxide in which up to half of the lead oxide content may be replaced by barium oxide or strontium oxide.

3. The improvement as defined in claim 1 wherein said insulating covering includes an outer surface and closely spaced north and south magnetic poles on said outer surface with the flux lines between said poles extending outwardly from said surface.

4. The improvement as defined in claim 1 wherein said insulating covering is spaced from said conductor by an intermediate electrical insulating coating.

5. The improvement as defined in claim 1 wherein said insulating covering includes one flat continuous surface coextensive with said conductor, and closely spaced north and south magnetic poles on said surface with the flux lines between said poles extending outwardly from said surface.

6. An electrical conductor as defined in claim 5 wherein said permanent magnet material is selected from the group consisting of barium ferrite, bismuth manganese, lead ferrite, cobalt ferrite, cobalt platinum, and a material composed of 65 to 88 molecular percent iron oxide, 35 to 15 molecular percent lead oxide and 0.8 to 8 molecular percent silicon oxide, in which up to half of the lead oxide content may be replaced by barium oxide or strontium oxide.

7. An electrical conductor unit comprised of a plurality of parallel extending conductors having insulation thereon, a mounting body, said mounting body comprising finely divided permanent magnetic particles embedded within a flexible, plastic material, said particles having low permeability, said body having a first substantially flat surface and a second surface, said conductors located between said first and said second surfaces, said second surface having elongated depressions extending parallel to said conductors and substantially midway between adjacent conductors, said first surface having depressions extending parallel to said conductors and substantially midway between adjacent conductors, and said first surface having a plurality of closely spaced pairs of magnetic poles extending along the complete length of said conductors.

8. An electrical conductor unit to be magnetically secured to a ferro-magnetic base, comprising a mounting body, parallel extending conductors embedded in said body and insulated thereby, said body comprising finely divided permanent magnetic particles embedded within a flexible, plastic material, said particles having low permeability, said body having a first and a second sub stantially flat surface, said conductors located between said first and said second surfaces, and each of said surfaces having a plurality of closely spaced pairs of magnetic poles extending along the complete length of said conductor.

References Cited by the Examiner UNITED STATES PATENTS 2,234,068 3 1941 Wiseman.

2,461,201 2/1949 Ellis .1 24201.2 X 2,576,679 11/1951 Guillard 148 -103 2,589,766 3/ 1952 Bernstein 24--201.2 2,701,819 2/1955 Hirtle 174117 2,712,591 7/1955 Rogell 174117 2,721,717 10/1955 Wales 248206 2,762,777 9/1956 Went et a1. 25262 2,787,656 4/ 1957 Raisbeck 178-45 FOREIGN PATENTS 121,512 5/ 1946 Australia. 552,740 12/ 1956 Italy.

OTHER REFERENCES Adams et al., Journal of Applied Physics, November 1952.

JOHN F. BURNS, Primary Examiner.

JOHN P. WILDMAN, DARRELL L. CLAY,

LARAMIE E. ASKIN, Examiners. 

1. IN THE COMBINATION OF AN ELONGATED ELECTRICAL CONDUCTOR AND AN INSULATING COVERING THEREON, THE IMPROVEMENT COMPRISING: SAID COVERING BEING FORMED FROM A HARDENED, FLEXIBLE ELECTRICALLY INSULATING MATERIAL AND FINELY DIVIDED PERMANENTLY MAGNETIZABLE PARTICLES DISPERSED THROUGHOUT AND EMBEDDED WITHIN SAID MATERIAL, SAID PARTICLES BEING FORMED FROM A PERMANENT MAGNET MATERIAL HAVING A LOW PERMEABILITY AND A HIGH COERCIVITY, 